Nummular Dermatitis & TNF-Inhibitors

Nummular dermatitis (aka discoid eczema) has an incidence of 2 in 1000 people, mostly men in the age range of 55-65.  However, treatment with a TNF-inhibitor is also a risk factor.

Like many medical terms, the name nummular dermatitis  comes from Latin roots:

  • nummular – from nummus - coin
  • dermis – a layer of skin
  • itis – inflammation

So, nummular dermatitis is coin-shaped inflamed patches of skin.  This rash can itch and burn, even to the extent that it disrupts sleep.  Some people, however, are fortunate enough to skip the unpleasant sensations that typically accompany this unsightly rash (sometimes there are advantages to peripheral neuropathy).

This rash is not contagious.

Appearance

Nummular dermatitis begins as a group of blisters or tiny red dots.  It quickly becomes a round or oval-shaped patch of red (sometimes pink or brown) skin.  Multiple patches are possible; they can be as small as two millimeters, or as large as four inches.  The rash usually appears on the extremities (arms, legs, feet, hands) or torso.  Thankfully, it is rare for patches to appear on the face.

  

Diagnosis

This rash is unique in appearance and can often be diagnosed based on a visual examination.  Usually no expensive tests are needed, but occasionally the rash will look like ringworm, in which case a doctor might need to take a sample to make an accurate diagnosis.

Causes

There are no known causes of nummular dermatitis, however a Dutch study of RA patients done in 2005 showed that 25% of RA patients on TNF-inhibitors needed referral to a dermatologist, vs. 13% of RA patients who had never taken a TNF-inhibitor.  Fortunately, only a small number had nummular dermatitis.  Of note, hepatitic C patients treated with a TNF-inhibitor have an increased risk of nummular dermatitis.  It will be interesting to see the results of follow-up studies now that TNF-inhibitor use is more common in the treatment of RA.

Treatment

Home treatments aren’t enough to deal with nummular dermatitis. Without adequate treatment, this rash can stick around indefinitely. Even with medical treatment, the rash can take months to resolve – some sources say it sometimes takes a full year for the rash to go away.

The goal of treatment is to:

  • reduce inflammation
  • repair the skin
  • rehydrate the skin
  • if infected, treat the infection

Credit:  http://s252.photobucket.com/albums/hh18/Jane-emma18/?action=view&current=Gumby.jpg&newest=1To reduce inflammation, prescription-strength steroid cream or ointment can be rubbed into the rash two-three times daily.  Unless you are Gumby, if your rash is on your back, you will need assistance with the application.  Oral steroids can be used when topical steroids are ineffective (this also eliminates the need for an assistant).

To increase absorption, the steroid cream/ointment should be applied to wet skin – particularly after a shower or twenty-minute soak.  Following application of the topical medicine, a good moisturizer should be applied to wet skin.  Some people recommend covering the medicated areas (ie with plastic wrap) for an hour to hold in the moisture.  Gently pat yourself dry; do not rub with a towel and remove the steroid cream & moisturizer.

Another treatment option – when topical steroids fail – is light therapy (UVB).

Although home treatments alone can’t cure nummular dermatitis, there are a few things you can do.  Take good care of your skin and be sure to moisturize it well.  Also, avoid potential flare-triggers.

A few of the things that sometimes cause flare-ups of this condition are:

  • frequent use of detergents or harsh soaps
  • hot tub usage
  • extreme temperatures (very hot or very cold)
  • extremes in humidity (or lack thereof)
  • rough wool clothing
  • skin injury (ie cut, burn, or insect bite)
  • some medications  (examples include accutane, neomycin, and TNF-inhibitors)
  • sensitivity or allergy to rubber, nickel, cobalt, formaldehyde, or mercury

This means that if your routine is to take a long, hot shower first thing in the morning before dressing in a nice warm, wool sweater and cozy wool socks, you might need to modify your routine.  Make it a shorter lukewarm shower, apply a good moisturizer to your skin, then dress is loose cotton clothing.  If your workout routine later includes spending twenty minutes in a steam room, followed by half an hour soaking/stretching in a hot tub, followed by an hour in a swimming pool, ten minutes in the dry sauna, and then another hot shower, you’re intentionally doing five of the eight things you need to avoid.

See a doctor for accurate diagnosis and treatment if you suspect nummular dermatitis.

Vocabulary for Reading Medical Literature about Nummular Dermatitis

erythematous – red
papules – bumps
vesicles – very small blisters
pruritic – itchy
xerosis – abnormal dryness

References

Arthritis Research & Therapy
Medscape
Skinsight
American Academy of Dermatology
DermNet NZ
British Association of Dermatologists

Patient Perspective on Refills

Med renewal appointments are supposed to be quick.  How hard can it be to verify that everything is okay, then write a new prescription?

Although I’d love to have my pharmacy fax my doctor about my prescriptions, doctors want to periodically examine the patient before authorizing more refills.  It doesn’t take very long reading medblogs to realize that there’s a reason my doctor won’t okay refills over the phone (or fax).  Maybe something has changed and the dose needs to be tweaked.  Maybe the medicine isn’t effective, so a different one needs to be tried.  Medblogs are great for learning the reasons that doctors offices do some of the things they do.

It’s one thing to read about it in theory, it’s another to experience it.

At a recent appointment, I asked for a renewal on two prescriptions.  Simple, straightforward.  That was the whole purpose of the appointment; I figured it would take five minutes.

One medicine is a headache prophylactic that I’ve taken for three years.  As usual, my doctor asked about headaches.  Normally I say there have been none, then he writes the renewal.  This time, however, I mentioned that I’d been having headaches, but figured out that it was due to the muscle relaxant I’d been taking.  I quit taking it, and have had no headaches since then.

While this was good news in obtaining a renewal on that med, it threw a wrench in the works for the other medicine that I wanted more of.

That second medicine was to treat a rash.  That rash was thought to be from a medication interaction.  If you start taking a new medication and subsequently develop a rash, then it makes sense that the med might have caused the rash (especially when it’s listed as one of the med’s possible side effects).  It also makes sense that discontinuing that med would make the rash go away.  If you discontinue the med, but the rash continues to get worse, then maybe the rash was caused by something else.

I knew that, but I don’t care.   I don’t care what the rash is.  I don’t want to know.  I don’t want to go to more doctor’s appointments.  I don’t want to have more tests.  I don’t want to incur more expense.  I don’t want another diagnosis.  I am done!  All I wanted was for my doctor to write a prescription so I could refill my meds (so that I can have little round scars on my legs instead of ugly bleeding sores).

Apparently, good doctors care what a rash is, even when the patient would rather not know.  I don’t want to go to more doctor’s appointments – but I have a referral and the appointment is already scheduled.  I don’t want to have more tests – but the doctor will probably want to run some.  I don’t want to incur more medical expenses - but all of this is going to cost money.  I don’t want another diagnosis - but it looks like I’ll walk out of there with one anyway.

Last week I checked in at my FP‘s office expecting my doctor to renew two prescriptions in a very quick appointment.  He did write those prescriptions, but that half-hour appointment wasn’t quick.  This is incredibly frustrating.  Request for med renewals aren’t supposed to be snowball appointments.